This is an alternative way the ISS could be constructed by using ELV’s. It is a technical discussion and doesn’t go into financial or political aspects. The intent is to show that the shuttle paradigm would not be required to get us where we are at now. This scenario assumes that since there is no shuttle, resources would be available for some launch vehicle and manned spacecraft development in the 80’s and 90’s. These vehicles could have been available in the late 1990’s or even earlier since many shuttle payloads still would have needed to be launched.

Ground rule: The ISS configuration will be similar to the existing plan (ie, same size modules and trusses with the same layout)

Requirements:

1. Titan-IV, NLS, or EELV class booster. Any LV with the capability of approximately 45klb or so to ISS orbit. It will be called ICLV (ISS Construction LV) 2. Crew Transport Vehicle – Apollo derived or OSP, etc. 3. Logistics Transport Vehicle – the CTV modified for cargo or HTV type. Depends on the logistics requirements of the flight. The modified CTV version would be used for return logistics.4. Crew Launch Vehicle - Core of #1 or even purpose built for #2 and #3.5. Service Module with ARAD or OMV – could be derived from #2 but smaller. It provides attitude control, power and some propulsion to a launch package. Just what is needed to bring a launch package from insertion orbit to the ISS6. Russian supplied hardware (Soyuz, Progress) except where designated, is unchanged.7. US ARAD could have been developed in the same time frame since there is a requirement for it, unlike in the shuttle era. 8. All EVA’s are station based. Assembly sequence is adjusted to account for it.9. Modules and trusses (all hardware) are modified to be launched from ELV’s. The trunnions are removed and one end of the modules is modified to mate to the SM and take launch loads. Same with trusses. The ends of the trusses and modules need to be reengineered to allow for module to module and truss to truss mates. Not impossible, just some work10. Most of the assembly elements do not docked to the ISS. They just rendezvous with the station and one of the arms grapples the new piece.

Now the meat of the discussion:

In this scenario, the FGB is not really needed but it is in the ground rules and it has one mod. It carries a shuttle size RMS but with dual end effectors. PDGF’s are on the FGB and SM. Controls are in the FGB

1. FGB launch 2. SM launch, FGB docks with it3. PIRS launch and docks with SM. Early EVA’s are based from here4. Crew launched by Soyuz and mans ISS5. Node 1 is launched by ICLV with SM. It approaches the FGB and is grappled and attached. The EVA’s are then done from the PIRS6. CTV’s can now fly as needed for crew “reinforcement” for assembly or exchange and LTV’s provide logistics and outfitting support 7. Z1 and PMA3 delivered via ICLV. The PMA3 is attached to the Z1 for launch8. P6 on a ICLV9. Lab on a ICLV10. LTV’s with rack11. SSRMS on a ICLV12. airlock on a ICLV13. S0 on a ICLV14. MT and MBS 15. S1 on a ICLV16. and so on

This is just gross overview and there are minor detail issues that are overlooked which would be worked if this was reality.

I invite comments and discussion. I don’t believe that there are any real problems that would invalidate the premise that the shuttle isn’t needed*. Most would be covered by the previous statement.

Of course, if there was no shuttle, the “ISS” design would have been completely different and optimized around the spacecraft and launch vehicles that would be used.

* Additionally, the LTV’s could be used for precursor microgravity missions much like a FOTON.

Jim - 21/2/2008 9:18 AMOf course, if there was no shuttle, the “ISS” design would have been completely different and optimized around the spacecraft and launch vehicles that would be used.

I think this is the crucial point. If we had Saturn V, Ares V, or J-232 (or another 100T-class launcher), the fundamental design of ISS would have been entirely different. If we had only EELV-class launchers, the fundamental design of the modules would have been somewhat different.

Is the point of the discussion what would we have done if Columbia or another similar event had been the end of the STS program and most of the modules had already been built?

As for getting the SSRMS onboard could it not have been launched with Destiny or Quest, under Jim's scenario? Like how the JEM RMS is hitching a ride on Kibo in May on STS-125.

Also, regarding existing modules like Unity, Destiny, et al - couldn't the trunnion pins be attached to a structure with the OMV at the end and the OMV bearing the launch loads? And couldn't future proposed ISS additions (after shuttle retirement) be done in a fashion similar to Jim's scenario? I would think someone's done some studies about that.

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I'll even excitedly look forward to "flags and footprints" and suborbital missions. Just fly...somewhere.

Correct me if I'm wrong but I was always under the impression that the ISS (or some form of space station) was a way to help sell the Shuttle when Apollo was winding down. And that, ultimately, it was cut down to a fraction of what it was originally meant to be. Now if we never had the Shuttle it's interesting to imagine "what if." Would we have concentrated in LEO? If we kept some form of Saturn would the "ISS" have been a base on the moon?

Jim, one thing strike me about your scenario. The ISS would have been constructed faster (and maybe cheaper?) and would have been utilized sooner and for a longer period of time.

Is the point of the discussion what would we have done if Columbia or another similar event had been the end of the STS program and most of the modules had already been built?

This is to show that a shuttle or orbiter is not needed to build stations. It is to show that an RMS, airlock, large crew and payload bay (shuttle paradigm) were not required now and are not required in the future.

with the CEV, people are whing that it isn't as "functional" as the orbiter and keep wanting to stick an arm and airlock on it. They are not needed.

This is to show that a shuttle or orbiter is not needed to build stations. It is to show that an RMS, airlock, large crew and payload bay (shuttle paradigm) were not required now and are not required in the future.

The Russians have certainly proven that those things are not needed. However, I would argue that they are beneficial.

Is the point of the discussion what would we have done if Columbia or another similar event had been the end of the STS program and most of the modules had already been built?

This is to show that a shuttle or orbiter is not needed to build stations. It is to show that an RMS, airlock, large crew and payload bay (shuttle paradigm) were not required now and are not required in the future.

Okay...I thought there were stations built without the Shuttle - none as large as ISS, but isn't it obvious that it's doable if needed?

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with the CEV, people are whing that it isn't as "functional" as the orbiter and keep wanting to stick an arm and airlock on it. They are not needed.

That included me, but not for building stations - for repairing JWST and other such operations, should the need arise, and even then a much smaller total system - a little arm for a single person (more like a fishing rod), not for moving ISS modules around or capturing Hubble. I'm one of the few around here that wants to do more laps in LEO, and I want to do it in a station built by a J-232 without benefit of arms or EVAs for assembly - I certainly agree fully that the Shuttle approach to constructing ISS is not required, and I didn't realize there were people around that think there is no other way to construct a station.

For that matter, if we had kept it as "Space Station Freedom" in a more KSC-friendly orbital inclination and funded ASRM to completion, things would be drastically different as well. C'est la vie.

Granted that a 22° orbital inclination takes less energy to achieve than a 51° inclination, and thus for the same amount of energy that it takes to get to 51° you could lift more mass if you’re living in the 22° world (I think this is the point you are making). And granted that we are stuck with a 51° inclination because of Russian launch restrictions, that said I always thought that there is something to be gained by over-flying a greater percentage of the earth’s surface. It provides for a greater flexibility in doing observations of ecological changes and meteorological tracking. So, although the US was forced to follow the path of the first Proton launch vehicle it hasn’t all been for naught.

Jettisoning the array and replacing it with a new one would have been easier.

One other way I can come up with is to just fold the array so the tear would have been within reach without the OBSS, but this could have damaged the array even further.

But from a technical point of view, the shuttle proved to be an asset.If in the ISS-without-shuttle scenario the array was damaged too much during refolding, it would have required a new solar array and an extra launch.

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Don't ever become a pessimist... a pessimist is correct oftener than an optimist, but an optimist has more fun, and neither can stop the march of events. - Robert Heinlein